1. That the established way of looking at the situation is the only possible way because it is right.
2. That by working logically on the situation, you arrive at the best perception of it.
3. That it does not matter where you starts because if your logic or mathematics is good enough, you will eventually reach the correct answer.

Vertical Thinking	Lateral Thinking
preserves established way of things	recognises dominant polarising ideas
polarises	search for different way of looking at things
porceeds from one certainty to next	relaxation of rigid control of vertical thinking
fits into boxes	uses chance
breeds arrogance and smudginess	PO