15.1: SEPERATING TRUTH FROM FICTION

Truth and trust are both important. We will naturally tend to trust claims such as newspaper reports; but we should be wary of blindly accepting every claim. 

Students should be encouraged to be inquisitive about life yet maintain a sense of skepticism. 

15.2: JUSTIFICATION

Determining the validity and truth of a claim can be challenging. The knowledge required to have at least near certainty of a claim is uncommon. 

-A false can be justified (based on limited available information) 

-A false can be unjustified 

-A truth can be justified 
-A truth can be unjustified (based on limited available information) 

TRUTH VS. JUSTIFICATION

Having enough evidence and justification to properly evaluate a claim is crucial to Critical Thinking. 

15.3: Levels and standards 

Understanding the balance of probabilities is important.  

Categorical claims: not justified; something may or may not happen, often expressed mathematically.

Qualified claims: uses words/phrases that add or subtract from the central claim.

15.4: HOW DO WE JUDGE CLAIMS?
A claim has strong justification if it does the following: 

Convincing grounds can be given to help accept it.

3

Shows beyond reasonable doubt to be true.

1

Shows to have extremely high probability.

2

Plausible claim:  

Ask yourself: Is it reasonable to think that it could be true, and not “far-fetched"? 

Credible claim: 

Ask yourself: Is it supported by reliable evidence? Does it come from a reliable source?  

CLAIMS

15.5: Complex claims 

SIMPLE VS. COMPLEX CLAIMS

Simple claims examples:  

1. It’s sunny outside. 

2. Frogs are amphibians. 

3. Polar bears live in the Arctic. 

Complex claims examples: 

1. If it’s sunny outside, then there is a slim probability it will rain. 

2. Frogs are amphibians, because they require a moist environment to survive. 

3. Polar bears live in the Arctic, but their numbers might start decreasing due to climate change. 

15.6: Strong and weak claims 

The strength of a claim is based on how much is being claimed and how intensely the claim is made. 

• Strong claims can be true and justified. 

• Strong claims can be false and unjustified. 

• Weak claims can be true and justified. 

• Weak claims can be false and unjustified.