Back in the old paper-and-pencil days I often took the SAT in a classroom with students. I broke my rule of never speaking to anyone when a student sitting beside me discovered that his calculator wouldn’t work. Seeing his distress, I offered him my calculator. He turned down my offer saying, “I couldn’t do that. You are a Vietnam veteran who served our country. It wouldn’t be right of me to hurt your chance of going back to college and turning your life around.”
The student made an incorrect CONJECTURE about my life story based upon my age. Lacking complete information, he assumed that an older looking adult male must be taking the SAT to go to college. But his SUPPOSITION was wrong. While I am an older adult, I am not a Vietnam veteran and have several college degrees. I insisted the student use my calculator. He did and profusely thanked me after the test.
SAT test writers frequently use CONJECTURE and SUPPOSITION to describe situations where there are speculations based upon incomplete evidence. For example, prior to Mariner 2’s flyby, scientists could only make CONJECTURES about Venus. In another example, linguists were once forced to make SUPPOSITIONS about the usage of specific words. However, the creation of text corpora has enabled linguists to replace their SUPPOSITIONS with accurate data-based information.
CONJECTURE – speculation based on incomplete evidence
SUPPOSITION – speculation based on incomplete evidence