No blocks yet. ClickTap “Add block”.
1. Add blocks. Type statements inside, like p → q.
2. Pick premises: lasso-select them (drag on empty canvas), or hit ⊕ in a block’s header.
2. Pick premises: tap ⊕ in the header of each premise block.
3. Click a block to set it as the conclusion. The selected premises now entail it.
3. Tap another block to set it as the conclusion. The picked premises now entail it.
Move around: drag the canvas to pan, pinch to zoom, drag a block by its header.
Valid means: no case where all premises are true and the conclusion is false.
Trivial means: the conclusion is already one of the premises. Logically valid, but adds no new information.
Operators: ¬ ∧ ∨ → ↔, or type ! & | -> <->. Variables are letters like p, q.
A concluded block can itself be a premise in the next step. Chain steps to build longer arguments.