The recounting of what Mendel did makes a short story. The narrative form is similar to that of a parable told by Christ. In the New Testament the parable may take 10 verses, but the implications are such that volumes of exegesis are produced. First, we tell the story, leaving the exegesis for later.
Johann Mendel, born in 1822, entered the Augustinian Monastery in Brno, Czechoslovakia, in 1843 and took the name Gregor. His nervous disposition made psychological stress destructive to his health. His reaction to his duties as a priest -- visiting the sick and ministering to the dying -- were so violent that he was relieved of all pastoral duties. Instead, in 1849, he began teaching at the Gymnasium of Znaim. He was a successful teacher and well liked by students and staff. For a permanent appointment he needed to pass the examination for gymnasium teachers. He started taking the series of exams for the certificate in 1850, but failed part way through. By this time Mendel had distinguished himself as a teacher at the technical high school of Brno, and he was sent to the University of Vienna in 1851 to strengthen his foundations in natural science. Mendel studied experimental physics with Doppler, and with Ettinghausen, who was appointed to replace Doppler as Director of the Physical Institute after Doppler's death in 1853. Mendel acted for a time as demonstrator at the Physical Institute. Mendel returned to Brno in the Summer of 1853, and began teaching again at the Oberrealschule at Brno. For the next 16 years he taught physics and natural history while carrying out his experiments on peas. He applied to take the teacher's exam again in 1855, but he yielded to the stress by becoming ill at the start of the exam. He returned to Brno, and continued to teach as a temporary -- but excellent -- teacher until he became Abbot of the Monastery in 1868.
Food production is an important aspect of monastery life. Mendel had worked at breeding bees, and in the summer of 1856, having recovered sufficiently from the trauma of the ``Vienna exam'', he began his study of the genetics of domestic peas. Over a period of two years Mendel studied the propagation and behavior of 34 varieties of peas the seeds of which he had managed to collect from various suppliers of seeds. In the end of this initial period he selected 7 varieties that showed pure propagation of a clearly definable trait, such as seed color or texture, vine height and so on. During the 6 years of experiments with hybridizing these 7 varieties, Mendel continued to propagate 22 varieties without crossing, as controls.
Mendel accepted the lack of variability in the first hybrid cross as a fact; one trait was simply dominant. The first filial generation displays the characteristics of the dominant genes. The strategy is thus to tease from observations on the second filial generation facts that would allow one to describe the mechanism of genetic sexual reproduction.