The view that suppression of a concept within the scope of negation is not unconditional was originally introduced by Giora (2003, 2006; Giora and Fein 1999; Giora et al. 2007) via the retention hypothesis. Giora and her colleagues argue that negation does not necessarily suppress the concept within its scope. Instead, it often retains it for pragmatic considerations, both in the mind of the speaker and the addressee. The present study provides a quantitative corpus-based test for the retention hypothesis, that is the non-obligatoriness of suppression of negated concepts (also known as the negation as mitigation hypothesis, Giora 2003; Giora et al. 2005b), via a two-pronged method which combines corpus data and behavioral data. It focuses on the notion of polarity strength, which is a numerical value disclosing the degree of positivity or negativity associated with an adjective. A simple statistic which is introduced for the sake of this study – the Strength Index (SI) – naïvely assumes that canonical adjectives can be mitigated by replacing them with their negated antonyms, thus making it possible to attribute SI to them. SI is calculated for 8 canonical adjectival antonymous pairs of an emotive nature (such as good-bad). Depending on prior positive expectations, the retention hypothesis will gain support if the following results are obtained: Correlation between the SIs of unfavorable adjectives (e.g., bad) and behavioral data on the one hand, and the lack of correlation between the SIs of favorable adjectives (e.g., good) and behavioral data, on the other hand. Results attest to this correlation pattern, providing support for the retention hypothesis (see also Colston 1999).