Search for tag: "introduction"

CL - Barbara

Gentzen's rules provide a complete system that does not require the cut rule. For many logical systems, cut elimination (showing that uses of the cut rule may be eliminated from any sound proof)…

From  Haoran Peng on October 21st, 2020 0 likes 15 plays 0  

CL - Implication

We derive the implication rule using the rules introduced last week.

From  Haoran Peng on October 20th, 2020 0 likes 73 plays 0  

CL - Sequents

We introduce sequents, where we have finite sets of predicates on both sides of the turnstile.

From  Haoran Peng on October 20th, 2020 0 likes 73 plays 0  

CL - Review 2 - Venn Apples

Venn diagrams on a sphere.

From  Haoran Peng on October 20th, 2020 0 likes 77 plays 0  

CL - Review 1 - Contraposition

We show the intuition of contraposition using Venn diagrams.

From  Haoran Peng on October 20th, 2020 0 likes 79 plays 0  

CL - Q&A - Thursday Week 4

In week 4 we introduced Gentzen's sequents.You should make sure you understand when a sequent is valid, and what it means to provide a counter-example to a sequent -- a universe in which the…

From  Haoran Peng on October 20th, 2020 0 likes 71 plays 0  

FP - Lecture 10 - Expression Trees as Algebraic Data Types

This is the video for the 10th FP lecture.

From  Claudia-Elena Chirita on October 19th, 2020 0 likes 73 plays 0  

FP - Lecture 9 - Expression Trees as Algebraic Data Types

This is the video for the ninth FP lecture on Expression Trees as Algebraic Data Types.

From  Claudia-Elena Chirita on October 18th, 2020 0 likes 107 plays 0  

CL - Lecture 4.k - Logic and Algebra

Last CL video for week 4.

From  Claudia-Elena Chirita on October 15th, 2020 0 likes 225 plays 0  

CL - Lecture 4.i - Reduction 1

We use the rules to reduce a sequent to a conjunction of simpler sequents. In this example we find that the expression asserted by the sequent is a tautology — it is equivalent to the empty…

From  Claudia-Elena Chirita on October 15th, 2020 0 likes 307 plays 0  

CL - Lecture 4.j - Reduction 2

We use the rules to reduce a sequent to a conjunction of simple sequents, sequents that only mentions propositional letters, with no connectives, and no repetitions — in this example, we find…

From  Claudia-Elena Chirita on October 15th, 2020 0 likes 266 plays 0  

CL - Lecture 4.h - Sequents 3

We can now give Gentzen's rules for ¬ ⋀ ⋁.

From  Claudia-Elena Chirita on October 15th, 2020 0 likes 285 plays 0  

CL - Lecture 4.g - Sequents 2

Additional predicates after the turnstile behave similarly.

From  Claudia-Elena Chirita on October 15th, 2020 0 likes 290 plays 0  

CL - Lecture 4.e - Sequents 0

The following videos introduce sequents, a far-reaching generalisation of the idea underlying Aristotle's propositions. We have already discussed the introduction of multiple antecedents…

From  Claudia-Elena Chirita on October 15th, 2020 0 likes 316 plays 0  

CL - Lecture 4d - Disjunction

In this video, we try to arrive at the disjunction rule.

From  Haoran Peng on October 11th, 2020 0 likes 404 plays 0