query: What is the first step in the dialectical method?
passage: Dialectic
Within Hegelianism, the word dialectic has the specialised meaning of a contradiction between ideas that serves as the determining factor in their relationship. Dialectic comprises three stages of development: first, a thesis or statement of an idea, which gives rise to a second step, a reaction or antithesis that contradicts or negates the thesis, and third, the synthesis, a statement through which the differences between the two points are resolved. Dialectical materialism, a theory or set of theories produced mainly by Karl Marx and Friedrich Engels, adapted the Hegelian dialectic into arguments regarding traditional materialism.
passage: Detection limit
Oftentimes there is more to the analytical method than just performing a reaction or submitting it to direct analysis. For example, it might be necessary to heat a sample that is to be analyzed for a particular metal with the addition of acid first (this is called digestion). The sample may also be diluted or concentrated prior to analysis on an instrument. Additional steps in an analysis add additional opportunities for error. Since detection limits are defined in terms of error, this will naturally increase the measured detection limit. This detection limit (with all steps of the analysis included) is called the MDL. The practical method for determining the MDL is to analyze 7 samples of concentration near the expected limit of detection. The standard deviation is then determined. The one-sided t-distribution is determined and multiplied versus the determined standard deviation. For seven samples (with six degrees of freedom) the t value for a 99% confidence level is 3.14. Rather than performing the complete analysis of seven identical samples, if the Instrument Detection Limit is known, the MDL may be estimated by multiplying the Instrument Detection Limit or Lower Level of Detection by the dilution prior to analyzing the sample solution on the instrument. This estimation, however, ignores any uncertainty that arises from performing the sample preparation and will therefore probably underestimate the true MDL.