← HCS syllabus
HCS (Haryana)Stage 1: Preliminary Examination
Logical Reasoning and Analytical Ability
What the official syllabus says
CSAT (Preliminary Examination, Paper II):
- Logical reasoning and analytical ability.
Topics in detail
Deductive logic
- Syllogisms: categorical statements (all, some, no, some not) and their conclusions
- Using Venn diagrams to test conclusions; "either-or" and "possibility" cases
- Conditional statements: if-then, only if, unless; the contrapositive
- Necessary and sufficient conditions
- Logical connectives: and, or, not; negation of statements
Critical reasoning
- Statement and assumptions: which assumptions are implicit
- Statement and conclusions: which conclusions definitely follow
- Statement and arguments: strong and weak arguments
- Statement and course of action: which action is practical and follows
- Cause and effect: independent causes, common causes, effects
- Strengthening and weakening an argument
- Inferences from a short passage: definitely true, probably true, false, data inadequate
- Assertion and reason questions
Analytical puzzles
- Linear arrangements: people in a row facing one direction or both
- Circular and rectangular seating arrangements
- Ordering and ranking by height, weight, age or marks
- Scheduling: days of the week, months, floors of a building
- Grouping and selection with conditions (who goes with whom)
- Matching puzzles with several attributes (person, city, profession, colour)
- Comparison and inequality statements
Analytical ability
- Breaking a problem into parts and recording the given conditions in a table or diagram
- Separating definite information from possibilities
- Checking each option against all the conditions
- Drawing conclusions from incomplete information
- Spotting contradictions and inconsistencies in a set of statements
Syllogisms: the four statement forms
| Form | Example | What follows with certainty |
|---|---|---|
| All A are B | All doctors are graduates | Some graduates are doctors |
| No A is B | No fish is a mammal | No mammal is a fish |
| Some A are B | Some officers are athletes | Some athletes are officers |
| Some A are not B | Some birds are not flyers | No simple conversion follows |
Assumption, inference and conclusion
- Assumption: something the speaker takes for granted without stating it. Test: if it were false, would the statement lose its sense?
- Inference: something that can be drawn from the facts given, with varying certainty.
- Conclusion: something that must follow from the statements alone, without outside facts.
- Strong argument: one that is relevant, important and directly about the question; a weak one is trivial, emotional or only loosely connected.
For puzzles, the reliable method is to draw the arrangement, place the definite clues first, then work out the possible cases for the conditional clues and eliminate those that break any condition.
Overlaps
Reasoning and analytical abilities are also named in the General Mental Ability part of Prelims General Studies. The topic sits next to General Mental Ability in this paper; the two are best prepared together.