Uploaded September 2021 | Updated September 2026, 5 hours ago
Embodied AI Lecture Series @ PRIOR
For previous recordings and upcoming talks visit prior.allenai.org/lectures
Biological Robots
Josh Bongard • University of Vermont • (8/20/21)
Abstract:
Reinforcement learning has greatly accelerated our ability to train control policies for robots. But, what if the robot has no observable control policy? --and is a millimeter in diameter? --and is composed solely from biological cells? The emerging field of computer designed organisms challenges our deepest preconceptions about how to apply AI methods to embodied machines, while simultaneously offering new materials and methods for building and reasoning about the nature of planning, control, decision making, agency, and general intelligence. In this talk I will describe how our team combined evolutionary algorithms with physical simulation to “program” behavior into biobots in silico, instantiate some of the most promising designs as physical biobots, and feed back lessons learned to improve subsequent sim2real transfers. I will conclude by discussing some of the implications of this work for biologists, the artificial intelligence community, and cognitive scientists.
Embodied AI Lecture Series @ PRIOR
For previous recordings and upcoming talks visit prior.allenai.org/lectures
Biological Robots
Josh Bongard • University of Vermont • (8/20/21)
Abstract:
Reinforcement learning has greatly accelerated our ability to train control policies for robots. But, what if the robot has no observable control policy? --and is a millimeter in diameter? --and is composed solely from biological cells? The emerging field of computer designed organisms challenges our deepest preconceptions about how to apply AI methods to embodied machines, while simultaneously offering new materials and methods for building and reasoning about the nature of planning, control, decision making, agency, and general intelligence. In this talk I will describe how our team combined evolutionary algorithms with physical simulation to “program” behavior into biobots in silico, instantiate some of the most promising designs as physical biobots, and feed back lessons learned to improve subsequent sim2real transfers. I will conclude by discussing some of the implications of this work for biologists, the artificial intelligence community, and cognitive scientists.
![Transformers as Soft Reasoners over Language | AI2
Beginning with McCarthys Advice Taker (1959), AI has pursued the goal of providing a system with explicit, general knowledge and having the system reason over that knowledge. However, expressing the knowledge in a formal (logical or probabilistic) representation has been a major obstacle to this research. This paper investigates a modern approach to this problem where the facts and rules are provided as natural language sentences, thus bypassing a formal representation. We train transformers to reason (or emulate reasoning) over these sentences using synthetically generated data. We provide the first empirical demonstration that this kind of soft reasoning over language is learnable and can achieve high (99%) accuracy, and in a way that generalizes to test data requiring substantially deeper chaining than seen during training (95%+ scores). We also demonstrate that the models transfer well to two hand-authored rulebases, and to rulebases paraphrased into more natural language. These findings are significant as it suggests a new role for transformers, namely as limited ``soft theorem provers operating over explicit theories in language. This in turn suggests new possibilities for explainability, correctability, and counterfactual reasoning in question-answering.
[IJCAI20 paper at https://www.ijcai.org/proceedings/2020/537] Transformers as Soft Reasoners over Language | AI2](https://i.ytimg.com/vi/P5KS0qj1eqc/mqdefault.jpg)




![Explaining Answers with Entailment Trees
Explaining Answers with Entailment Trees
Bhavana Dalvi
https://allenai.org/team/bhavanad
Our goal, in the context of open-domain textual question-answering (QA), is to explain answers by showing the line of reasoning from what is known to the answer, rather than simply showing a fragment of textual evidence (a rationale). If this could be done, new opportunities for understanding and debugging the systems reasoning become possible. Our approach is to generate explanations in the form of entailment trees, namely a tree of multipremise entailment steps from facts that are known, through intermediate conclusions, to the hypothesis of interest (namely the question + answer). To train a model with this skill, we created ENTAILMENTBANK, the first dataset to contain multistep entailment trees. Given a hypothesis (question + answer), we define three increasingly difficult explanation tasks: generate a valid entailment tree given (a) all relevant sentences (b) all relevant and some irrelevant sentences, or (c) a corpus. We show that a strong language model can partially solve these tasks, in particular when the relevant sentences are included in the input (e.g., 35% of trees for (a) are perfect), and with indications of generalization to other domains. This work is significant as it provides a new type of dataset (multistep entailments) and baselines, offering a new avenue for the community to generate richer, more systematic explanations. [ Paper published in EMNLP 2021, https://arxiv.org/abs/2104.08661 ] Explaining Answers with Entailment Trees](https://i.ytimg.com/vi/QPSZQYA1RmA/mqdefault.jpg)




