Informatica 42 (2018) 77–84 77 Towards Creative Software Blending: Computational Infrastructure and Use Cases Matej Martinc1,2, Martin Žnidaršič1, Nada Lavrač1,3 and Senja Pollak1 1 Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia 2 Jožef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia 3 University of Nova Gorica, Nova Gorica, Slovenia E-mail: matej.martinc@ijs.si, nada.lavrac@ijs.si, martin.znidarsic@ijs.si, senja.pollak@ijs.si Keywords: computational creativity, software blending, visual programming platforms Received: October 31, 2017 Numerous visual programming platforms support the generation, execution and reuse of constructed scien- tific workflows. However, there has been little effort devoted to building creative software blending sys- tems, capable of composing novel workflows by autonomously combining individual software components or even entire workflows originally designed for solving tasks in different research fields. Based on the review of relevant computational creativity research and of contemporary web platforms for workflow construction, this paper defines the desired functionality of a software blending system. Considering the required autonomy of the system and the workflow complexity limitations, we investigate the necessary conditions for the implementation of a creative blending system within the existing visual programming platforms. Povzetek: Številne platforme za vizualno programiranje podpirajo gradnjo, izvajanje in ponovno uporabo zgrajenih znanstvenih delotokov. Dosedanje raziskave niso posvečale pozornosti izdelavi kreativnih siste- mov za spajanje programske opreme, ki bi bili sposobni avtonomnega sestavljanja posameznih program- skih komponent ali celo celotnih delotokov, prvotno izdelanih za reševanje nalog na različnih znanstvenih področjih. Na podlagi pregleda raziskav s področja računalniške ustvarjalnosti in obstoječih spletnih plat- form za gradnjo delotokov v tem članku definiramo želeno funkcionalnost sistema za kreativno spajanje programske opreme. Upoštevaje zahteve po avtonomnosti sistema in dovoljeno kompleksnost delotokov preučimo tudi pogoje za implementacijo takega sistema v obstoječih platformah za vizualno programiranje. 1 Introduction Creativity was defined by M. Boden [3] as “the ability to come up with ideas or artefacts that are new, surprising, and valuable”. It is considered as an aspect of human intel- ligence, grounded in everyday abilities such as conceptual thinking, perception, memory and reflective self-criticism. Software is usually not considered creative because it follows explicit instructions of the programmer [4]. Ho- wever, writing software is considered to be a creative task. If a program could define its own instructions, this would clearly mean that the program has some level of creativity. A subfield of artificial intelligence has recently emerged, in which one of the main goals is the creation of software that is able to model, simulate or replicate human creativity. This field, called computational creativity, has been defi- ned by S. Colton and G. Wiggins [6] as “the philosophy, science and engineering of computational systems which, by taking on particular responsibilities, exhibit behaviours that unbiased observers would deem to be creative.” Note that the field of computational creativity should not be confused with the field of creative computing. Alt- hough these two research areas partly overlap, creative computing differs from computational creativity by gene- rally not being considered as a subfield of artificial intel- ligence, since it mostly addresses the task of creative de- velopment of computing products and with how to write software that would better serve the needs of the creative community [13]. Infrastructures supporting computational creativity and the generation of creative systems are scarce, although some recent research attempts has tried to fill this gap. One of the recent developments is FloWr [4], a system for im- plementing creative systems as scripts over processes and manipulated visually as flowcharts. Another is the Con- CreTeFlows infrastructure [27], which was developed to enable the construction, sharing and execution of compu- tational creativity (CC) workflows, composed of software ingredients of different partners of European project Con- CreTe1. Both of these infrastructures use different types of resources (e.g., musical, pictorial and textual inputs) in order to support the development of some typical CC task such as poetry generation, metaphor creation, generation of narratives, creation of fictional ideas and conceptual blen- ding. 1http://conceptcreationtechnology.eu 78 Informatica 42 (2018) 77–84 M. Martinc et al. These platforms, which enable the user to build procedu- res capable of producing a variety of different creative arte- facts, could hardly be called creative systems, since they do not exhibit creative behavior in terms of automated work- flow development. The arguably most creative system for automated workflow construction, optimization and altera- tion, which is implemented in the FloWr platform, requires a lot of manual user input and could only be called creative with some major reservations. To fill the identified gap, this paper addresses the task of developing an infrastructure capable of autonomously composing novel scientific workflows by creatively combi- ning individual software components or even entire work- flows originally designed for specific tasks in different rese- arch fields. We consider the process of autonomous work- flow composition—which we name creative software blen- ding in this paper—to be an important first step towards a long term goal of creating software that could write code directly. The proposed system would be able to bridge dif- ferent scientific fields by combining methods from specific fields into novel interdisciplinary workflows. It would ide- ally also be capable of automated interdisciplinary research by autonomously discovering novel scientific procedures. This paper presents the design principles underlying a creative system described above. Section 2 introduces the research topic and presents the infrastructures suitable for the implementation of a creative software blending system. Section 3 motivates this research by presenting two exis- ting hand-blended workflows. Section 4 presents the re- lated software blending and computational creativity rese- arch, followed by an outline of the desired system functi- onality, investigating the necessary conditions for the im- plementation of a creative system for autonomous creative workflow generation. The paper concludes by presenting plans for future work. 2 Research background and infrastructures As background to our creative software blending research, this section first outlines some creativity support tools, fol- lowed by a brief description of a selection of easy-to-use workflow management systems that allow the user to com- pose complex computational pipelines in a modular visual programming manner. 2.1 Creative software As Colton’s and Wiggins’ definition of computational cre- ativity [6] is hardly operational for measuring creativity of a program, G. Ritchie [23] proposed some empirical crite- ria for attributing creativity to a computer program. The main idea is to use empirically observable and comparable factors, such as the properties of the generated output of the creative system, when trying to assess the creativity of a system. These observable factors can be judged by two quantifiable and essential criteria: Novelty of an output determines to what extent is the produced item dissimilar to existing examples of its genre. Quality of an output determines to what extent is the pro- duced item a high quality example of its genre. Using these criteria, we can say that the system for cre- ative software blending is creative if it outputs novel and high quality scientific workflows. Another relevant question is what types of creative beha- viors exist and how can they be computationally modeled. Boden [3] distinguishes three basic types of creativity: Combinational creativity involves making unfamiliar combinations of familiar ideas. Exploratory creativity involves exploration of a concep- tual space, which is characterized as a structured style of thought, and coming up with a new idea or artefact within that thinking style. Transformational creativity refers to the modification of the conceptual space so that new kinds of ideas and artefacts can be generated. Combinational creativity is the easiest one to be modeled on a computer. However, created combinations should be meaningful and interesting, which usually requires a solid background knowledge and the ability to form and evaluate relations of many different types. Several programs exist that can explore a given space and invent new artefacts with a certain style, for example, a program for automatic music generation [19] or a program for generating game designs [7]. Some programs can even transform their conceptual space by altering their own rules; for example, evolutionary algorithms can make random changes in their current rules and by this evolve new structures. Another important distinction made by Boden [3] is a distinction between psychological creativity (P-creativity) and historical creativity (H-creativity). P-creativity rela- tes to creation of surprising, valuable ideas and artefacts that are new to the person who comes up with it. Howe- ver, if an artefact or idea has arisen for the first time in human history and (so far as we know) nobody else has had it before, then we are talking about H-creativity. We anticipate that if the targeted creative software blending sy- stem is to be an active participant in scientific discovery or artefact creation, it should ideally be H-creative, although even a P-creative system can play a very useful supporting role in scientific research and its development is therefore a worthy research goal. 2.2 Infrastructures A system for creative software blending would best be im- plemented inside an already existing infrastructure ena- bling interdisciplinary and creative scientific workflow Towards Creative Software Blending. . . Informatica 42 (2018) 77–84 79 composition. In this section we present the ClowdFlows and ConCreTeFlows platforms that host the two motivatio- nal use cases, but other platforms, such as FloWr [4], Ra- pid Miner [18], KNIME [2], ORANGE [8] are also worth exploring as potential infrastructures for creative software blending. ClowdFlows [16] is a cloud-based web application2 for composition, execution and sharing of interactive data mining workflows. It has a web based user interface for building workflows, runs in all major browsers and requires no installation. It contains a large set of work- flow components called widgets, which can be con- nected in a specific meaningful order to create a work- flow. ClowdFlows enables visual programming and has a graphical user interface which consists of a wid- get repository and a workflow canvas. ConCreTeFlows [27] is a platform3 built on top of the ClowdFlows infrastructure. It is specialized in com- putational creativity tasks, including conceptual blen- ding based on textual or visual input or text generation tasks, such as poetry generation. The specialization of ConCreTeFlows in computational (and especially text-based) creativity, as well as a smal- ler number of implemented widgets, makes it less appro- priate for the implementation of the proposed system for creative software blending, but it is appropriate to show- case the creative blending process. On the other hand, ClowdFlows is not specialized in a single specific rese- arch field and contains widgets from the fields of text mi- ning, machine learning and NLP, which makes it appro- priate for the implementation of a creative software blen- ding system since combining tools from different research fields would most likely increase the chance of the sy- stem to be H-creative. As a basis of automated software composition, ClowdFlows already includes a—somewhat loosely defined—ontology of its components (named wid- gets), which should be enhanced and elaborated in further work, to enable ClowdFlows to actually become a useful infrastructure for software blending. 3 Motivational use cases This section presents two hand-crafted motivational work- flows, which illustrate the usefulness of blending software from different scientific fields in order to develop new in- novative scientific methods. In this sense, they represent the type of workflows that a system for creative software blending would be capable to produce. 3.1 Wordification use case: Blending data mining and text mining in ClowdFlows Propositionalization [15] is an approach to inductive lo- gic programming (ILP) and relational data mining (RDM), which offers a way to transform a relational database into a propositional single-table format. Consequently, learning with propositionalization techniques is divided into two self-contained phases: (1) transformation of relational data into a single-table format and (2) selecting and applying a propositional learner to the transformed data set. As an ad- vantage, propositionalization is not limited to specific data mining tasks such as classification, which is usually the case with ILP and RDM methods that directly induce pre- dictive models from relational data. This section motivates creative software blending by outlining the Wordification workflow [22], implemented in ClowdFlows, which per- forms propositionalization by combining data mining and text mining techniques. In the Wordification workflow, shown in Figure 1, given a MySQL relational database as input, the user selects the target table from the initial relational database, which will later represent the main table in the Wordification compo- nent of the workflow. The user is able to discretize each of the tables using one of the available discretization techni- ques. These discretized tables are used by the Wordifica- tion widget, where the transformation from the relational tables to a ‘corpus of documents’ is performed. Several elements of blending data mining and text mi- ning techniques are incorporated in the Wordification: i.e. transforming attribute values into bags of word-like items, using TF-IDF weighting of items, and the possibility of using n-grams of items where n-gram construction is per- formed by taking every combination of length n of items from the set of all items corresponding to the given indivi- dual. Nevertheless, the element of the workflow that most clearly illustrates the software blending potential is the in- clusion of a word cloud visualization (an approach deve- loped in text mining research), together with decision tree construction and visualization (an approach developed in data mining research). 3.2 Conceptual blending use case: computational creativity in ConCreTeFlows The elements of the conceptual blending theory [12], des- cribed in more detail in Section 4, are an inspiration to many algorithms and methodologies in the field of com- putational creativity. In brief, according to this theory, two different concepts for which we can define (find) a simila- rity, can be blended into a new concept in the context of knowledge that is necessary to represent and generalize the two concepts. 2Available at http://clowdflows.org 3Available at http://concreteflows.ijs.si 80 Informatica 42 (2018) 77–84 M. Martinc et al. Figure 1: Clowdflows Wordification workflow with additional analyses after the wordification process, available at http: //clowdflows.org/workflow/1455/. Figure 2: Workflow implementation of multimodal blending in ConCreTeFlows, available at: http://concreteflows.ijs.si/workflow/137/. Let us present a conceptual blending CC workflow [27], implemented in the ConCreTeFlows platform by different partners of the ConCreTe project. Its process components are implemented either as internal functions, wrapped stan- dalone programs or as Web services. The publicly available workflow, presented in Figure 2, can be executed, changed and extended with additional functionality. The workflow presents conceptual blending by con- structing conceptual graphs from textual input and repre- senting the results (blends) as graphs, natural language des- criptions and visual representations. Two textual inputs are transformed into conceptual graphs by a series of wid- gets: the Download web page for obtaining the Web page source from a given URL (In the example, these are the Wikipedia pages for two animals: hamster and zebra.), Boi- lerplate removal and Text2Graph transforming the textual content into conceptual graphs (output g). The outputs of Text2Graph widgets enter Blender basic, which blends the two graphs together and outputs a combined blended graph (output bg). This one gets served to the Textifier widget, which produces a textual description of the blend. Its out- put is presented by a standard Display String widget. The two main entities from Text2Graph widgets enter also the Vismantic2 visual blending widget [28], which either chan- ges the texture of one input space to the texture of the other (see Figure 3a), or puts one in the usual surroundings of the other. (Figure 3b). Its outcome is shown in an output similar to the ones shown in Figure 3. 4 Towards design principles for creative software blending There are two major paradigms in artificial intelligence re- search: problem solving and artefact generation [5]. While the problem solving paradigm deals with a series of pro- blems that needs to be solved, in the artefact generation pa- radigm the task is to generate a series of valuable artefacts. This study is more related to the latter and the artefacts of our interest are functional workflows. A creative software blending system should be able to build new workflows composed of software components from different fields, leading to novel ways of software composition for computational purposes that were not ex- pected in advance. Such blending of software would best be implemented in an existing infrastructure for interdisci- plinary scientific research with already implemented com- ponents for specific and well defined tasks. As shown in Section 2.2, much effort in the fields of data mining and NLP has already been devoted to the de- velopment of infrastructures that provide support for easier and quicker experimentation. One of the biggest challen- Towards Creative Software Blending. . . Informatica 42 (2018) 77–84 81 (a) (b) Figure 3: Two outputs of the Vismantic2 widget for the example of blending the concepts of hamster and zebra: left is a result of exchanging hamster’s texture with zebra’s and the right is an example of exchanging zebra’s with a hamster’s common visual context. ges in implementation and use of these infrastructures has been the integration of different components into functio- nal workflows. Combining different tools and technologies in a common infrastructure is a difficult task because of software incompatibility and inappropriately defined onto- logies. 4.1 Related software blending research To design an appropriate creative software blending system one should consider three fields of study. First, one has to reflect upon the concept of creativity and how to build soft- ware that exhibits creative behavior (see the related rese- arch in Section 2.1). Next, one has to be aware of strengths and limitations of the existing infrastructures that could be used as a platform for the implementation of our system (see the related infrastructures in Section 2.2). Finally, one has to become aware of potentially existing implemented approaches for software blending, surveyed below. While the FloWr framework [4] is conceptually very si- milar to the two infrastructures described in Section 2.2, it is currently the only one with a specifically defined aim of being able to automatically optimize, alter and ulti- mately generate novel workflows presented as flowcharts. This automatic workflow generation via the combination of code modules means that FloWr has the potential to in- novate at the process level and the manifested long-term goal is a software system that can write program code for itself [4]. Although the platform currently does not sup- port fully functioning software blending, some preliminary experiments to automatically alter, optimize and generate flowcharts have been conducted. One of the FloWr experiments dealt with an automatic construction of a system for producing poetic couplets from scratch. In order to reduce the number of possible com- binations of different workflow components, only a sub- set of all the available components were manually selected for blending in the experiment. Possible options for the input parameters were manually reduced and the number of components in the generated workflow was limited to 3 to 5. Despite these limitations, at the end there were still over 261 million variable definition combinations. For this reason the brute-force approach of testing all combinati- ons was intractable, so a depth-first search for all possible workflows was implemented in a way that just one node combination and one parameter setting were randomly se- lected from a set of allowed combinations. The compati- bility of sequential components and some other restrictions were taken into account, which reduced the number of pos- sible workflow candidates. The algorithm was run 200 ti- mes resulting in 200 workflows. A manual evaluation sho- wed that 18.5% of workflows worked successfully and pro- duced poetic couplets.The conducted experiment required a lot of human intervention in order to be successful and the evaluation of produced artefacts was done by humans. Because of this we can question the creativity of the propo- sed software blending approach since a software should — at least in our opinion — have the capacity to evaluate its own performance in order to be called creative. While FloWr belongs to CC research, several attempts have been made to develop support systems also in the field of knowledge discovery. These systems are to some extent related to our research, since they either support the users workflow composition by recommending the new compo- nents that could be attached to an existing workflow, or by generating entire workflows according to user require- ments. Zakova et al. [26] proposed a semi-automatic system for workflow generation that is based on a background know- ledge ontology in which all workflow components are des- cribed together with their inputs, outputs and pre-/post con- ditions. The system uses a planning algorithm and returns just one optimal workflow with the smallest number of pro- cessing steps. Given that alternative workflows are not ge- nerated, this is not in accordance with a desired system for creative software blending. Complexity limitations are another problem, which is common to all the systems that use planning approaches for workflow generation. The IDEA system by Bernstein et al. [1] is based on an ontology of data mining components that guides the work- flow composition and contains heuristics for the rankings of different alternatives. The system does not enable fully 82 Informatica 42 (2018) 77–84 M. Martinc et al. Figure 4: The conceptual blending network [11]. automatic workflow generation but was implemented as a support system for the user who decides on the weights to determine the trade-off between different performance cri- teria (e.g., speed, accuracy, comprehensibility). IDEA is limited to proposing fairly simple workflows. Kietz et al. [14] proposed a KDD support system that uses a data mining ontology. The ontology contains infor- mation about the objects manipulated, the meta data, the operators (i.e. components containing algorithms for spe- cific tasks) and a description of the goal, which is a for- malization of the user desired output. The system takes a goal description as an input and returns a workflow toget- her with all the evaluation and reporting needed to let the user assess if it fulfills the user defined success criterion. The system, implemented in the RapidMiner platform, is not fully autonomous, as it was designed as a support sy- stem for the user. 4.2 Design principles As the above survey shows, no adequate solution for the au- tonomous creative software blending currently exists. To build such a system, first, an ontology with well-defined rules and relations needs to be created, in order to ena- ble combining software components in a meaningful way. Next, a system for creative blending of software compo- nents would be created, enabling automated combination of components in functional workflows. Computational creativity, which is still in early phrases of its development [25], provides some methodological ap- paratus and inspiration for designing the guiding princi- ples for a creative software blending system. One of the very productive fields of research in computational crea- tivity is the conceptual blending (CB) theory [12], which inspired many algorithms, methodologies and discussions in the field (e.g., [24, 21, 17]). CB is a basic mental operation that leads to new mea- ning, global insight, and conceptual compressions useful for memory and manipulation of otherwise diffuse ranges of meaning [9]. A key element is the mental space, a partial and temporary structure of knowledge built for the purpose of local understanding and action [10]. To describe the CB process, the theory [12] makes use of a network of four mental spaces (see Figure 4). In blending, structure from two input mental spaces (Input I1, Input I2), is projected to a new space, the blend. A partial mapping between elements of input spaces—that are perceived as similar or analogous in some respect—is performed. The third mental space, called generic space, encapsulates the conceptual structure shared by the input spaces, generali- zing and possibly enriching them. This space provides gui- dance to the next step, where elements from each of the in- put spaces are selectively projected into the blend, i.e. the new blended mental space. Emergent structure arises in the blend that is not copied there directly from any input. The conceptual blending model is not directly transfe- rable from the human cognition to the blending of soft- ware. However, the methodology, together with the opti- mality principles [11] that optimize the blending process— which were already addressed also in computational mo- dels [20]—should be considered when implementing the software blending algorithm and the workflow ontology. For example, in software blending the two inputs would not represent concepts but rather two workflows from two dif- ferent scientific domains. The “generic space” could then be adapted to software blending in order for the blending system to find all the compatible widgets from two diffe- rent input workflow domains. Finally, the blend would be a newly produced workflow containing new emergent struc- tures not copied from original workflows. The optimality principles, such as the relevance principle (which dictates that all elements in the blend should be relevant) and inte- gration principle (which states that the final blend should be perceived as an enclosed unit) should be kept in mind when designing the ontology. Another important aspect to be considered in the imple- mentation of the system is its creative part. In order for the system to be recognized as creative, its produced artefacts should be novel and of good quality [23] and the human interference in the production and evaluation of these ar- tefacts should be minimal. Three criteria are proposed for attributing creative autonomy to a system [25]: Autonomous evaluation The system should be able to evaluate new creations autonomously and possess its own “opinion” on which creations are better than ot- hers. Autonomous change The system should be able to change its evaluation function without explicit directi- ons. Non-Randomness (Aleatoricism) Random behavior is not creative, so evaluation and change should not be Towards Creative Software Blending. . . Informatica 42 (2018) 77–84 83 completely random, although some randomness can be involved. In order to satisfy these criteria and since most of the afo- rementioned platforms contain a large set of manually built workflows that could be used as a training set, we propose a combination of an evolutionary algorithm and a classifi- cation model induction. An evolutionary algorithm would operate directly on representations of workflows and gene- rate new workflow candidates, according to the constraints defined by ontology rules. These constraints would enforce a minimum quality for the produced workflows (correspon- ding to the criterion of quality [23], which is, as explained earlier, one of the guiding principles in the construction of creative artefacts). The initial population of the evolutionary algorithm would consist of manually built workflows that would be “blended” into new workflow candidates with the help of mutation and crossover. The fitness function used for eva- luating the fitness of the generated workflow candidates would contain following elements: A binary classification model trained on the features ex- tracted from successful and unsuccessful workflows would serve as an additional workflow quality check. A similarity function for determining the similarity be- tween a generated workflow candidate and existing workflow would be used for evaluating the novelty of the candidate. In this way the system would be able to generate new— possibly creative—workflows and even propose changes in the existing rules for workflow generation, which would make this system capable of transformational creativity ac- cording to [3]. 5 Conclusions In this study we elaborate the initial design principles of a system for automatic workflow generation that would be capable of autonomous composition of novel workflows from existing software components. We have presented two workflows with human-designed blending, implemen- ted in the ClowdFlows and ConCreTeFlows platforms for online workflow composition. The first workflow clearly illustrated the potential for the composition of computa- tional creativity solutions. The second use case presents several computational creativity software components that were combined in a collaborative effort to implement an interesting conceptual blending solution, resulting in con- ceptual, visual and textual blends. The benefits of a uni- fying workflow for blending are twofold: the user can get blends of various kinds through the same user interface and the components can affect one another to produce a more coherent and orchestrated set of multimodal blending re- sults. The presented prototype solution is fully operational and serves as a proof of concept that such an approach to multimodal conceptual blending is possible. On the other hand, the sketched evolutionary algorithm approach to blending workflows and workflow components shows, that the theory of conceptual blending can be trans- ferred to the problem of creative software blending. We also demonstrated that the system will be capable of self evaluation by using the empirical criteria of novelty and quality in the fitness function. In our future work we will first design an ontology capa- ble of supporting the planned widget recommender system. We also plan to integrate a larger number of widgets and workflows in the presented platforms. Moreover, we will undertake the challenging task of the implementation. We realize that creation of software that can innovate at a pro- cess level is a very demanding task and we can expect many challenges during this phase. Anyhow, we do believe that the effort will be fruitful and bring us closer to the long- term goal of creating software that could write novel and valuable code directly. Acknowledgments We acknowledge the support of the Slovenian Research Agency through research programme Knowledge Techno- logies (grant number P2-0103), and project ClowdFlows Data and Text Analytics Marketplace on the Web (CF- Web), which has received funding from the European Uni- ons Horizon 2020 research and innovation programme un- der grant agreement No 754549. We would like to thank Pedro Martins and Amilcar Cardoso for numerous discus- sions on the topic of conceptual blending. References [1] Bernstein, A., Provost, F., Hill, S.: Toward intelligent assistance for a data mining process: An ontology- based approach for cost-sensitive classification. IEEE Transactions on Knowledge and Data Engineering 17(4), 503–518 (2005) [2] Berthold, M.R., Cebron, N., Dill, F., Gabriel, T.R., Kötter, T., Meinl, T., Ohl, P., Thiel, K., Wiswedel, B.: Knime–the Konstanz Information Miner: Version 2.0 and beyond. 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