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Here's how I'd derive rule of explosion($\bot\vdash\varphi$) from MTP:

  1. $\;\bot$ --- premise
  2. $\;\varphi\vee\bot$ --- $\vee$ intro 1
  3. $\;\bullet\;\bot$ --- assumption
  4. $\;\bullet\;\bot$ --- reiteration 3
  5. $\;\neg\bot$ --- $\neg$ intro 3 - 4
  6. $\;\varphi$ --- MTP 2,5

Now is it fine and would you suggest any other way of derivation?

Pooria
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This all depends on what rules you have.

For example, in the proof you use $\lor$ Intro, reiteration, and $\neg$ Intro ... how do I know you have those rules available to you?

When you ask whether some proof exists or is correct, you need to tell us what rules you are allowed to use.

Bram28
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  • Well assume all rules I use are allowed and any proof in any natural deduction system you'd like is fine ^^ – Pooria Sep 27 '17 at 16:17