Présumer.
To arrive at by conjecture; to infer on slight evidence; to surmise; to guess; to form, at random, opinions concerning.
ETYM See Speculation (n.).
1. To indulge in speculations.
2. To invest at a risk; SYN. job.
3. To believe especially on uncertain or tentative grounds; SYN. theorize, theorise, conjecture, hypothesize, hypothecate, suppose.